1. Field of the Invention
This invention relates to a wood processing machine, and more particularly to a floating caterpillar feeder for a wood processing machine.
2. Description of the Related Art
When a wooden plate dries, it deforms to thereby have uneven side surfaces. When the deformed wooden plate is moved by a feeder under pressure on a worktable of a wood processing machine, such as a wood planing machine, not only can it not be moved smoothly, but also, the service life of the feeder is reduced.
Referring to FIGS. 1 and 2, a conventional caterpillar feeder is used for a wood planing machine, and includes a housing 1, a driving unit 2, and a plurality of feeding units 3 driven by the driving unit 2. Each feeding unit 3 includes a pair of inner and outer plates 302, 301, a plurality of support rods 303 connected fixedly between the inner and outer plates 302, 301, a plurality of pushing rods 304, and a plurality of springs 305. Each of the inner and outer plates 302, 301 has a plurality of holes 302′, 301′ for extension of the support rods 303 and the pushing rods 304. Each pushing rod 304 includes a rod body having a pushing end 306 disposed outwardly of the housing 1, and a retaining ring 307 sleeved fixedly on the rod body and abutting against an inner surface of the corresponding outer plate 301. Each spring 305 is disposed between the corresponding inner plate 302 and the retaining ring 307. When the feeding units 3 circulate, some of the pushing rods 304 come into frictional contact with a top surface of a wooden plate (not shown) for feeding the same at any time during circulation of the feeding units 3.
The aforesaid conventional caterpillar feeder suffers from the following disadvantages:    1. The inner and outer plates 302, 301 must be drilled to form the holes 302′, 301′, thereby resulting in a troublesome manufacturing process.    2. Since the holes 301′, 302′ are vertical when the corresponding feeding unit 3 is in contact with the wooden plate, wood shavings move upwardly into spaces between the corresponding outer plate 301 and the corresponding pushing rods 304 and between the corresponding pushing rods 304 and the corresponding springs 305, thereby affecting adversely smooth movement of the corresponding pushing rods 304 and, thus, the wooden plate.